The present invention relates to a connecting terminal having at least one receiving means for a base contact element for a screw connection. Moreover, the present invention relates to a connecting terminal having at least one spring-clamping means.
In connection with installation and industrial switching devices, in particular switching and protective devices such as contactors, motor protection switches, or the like, it is known to design connecting terminals with screw fixing and spring-clamping technology.
It is known from German Utility Model Patent DE 296 19 139 U1 to equip a connecting terminal with a cage clamp. To actually allow the clamping piece to be mounted in a switching device, no supporting segments can be arranged in the housing according to this design. In this connection, the installation is done from the front. The purpose of supporting segments is to absorb the forces occurring in the cage clamp. To eliminate this problem, the connecting piece features a punched-out retaining tongue. This requires an additional punching operation.
Such supporting segments exist in connecting terminals for bus bars as shown in German Utility Model Patent DE 93 15 474 U. Unlike the aforementioned terminal, the cage clamp is mounted from the side. In the case of switching devices, for example, contactors, this is not so easily possible. German Patent 197 56 751 C1 shows and describes a connecting terminal in which is located a bone-like retention piece around which is arranged the spring-tension clamp. Here too, the installation is carried out from the side. German Patent DE 43 21 067 C1 describes a connecting terminal for a printed-circuit board, featuring screw clamps which are arranged in steps, as shown in FIG. 6. German Patent DE 35 10 588 C2 shows a switching device featuring connecting terminals in screw technology.
Base contact elements which are arranged between separating segments are provided with a saw-toothing. Advantages ensue with respect to warehousing. This switching device is not intended for use of spring clamps.
Therefore, an object of the present invention is to provide a connecting terminal which is suitable for switching devices and which permits simple assembly, a further reduction in warehousing costs, while at the same allowing the use of both screw and clamping technology.
The present invention provides a connecting terminal for a switching device. The connecting terminal includes at least one receiving device configured to interchangeably receive either of a base contact element for a screw connection or a module for a spring-clamping device. A receiving shaft configured to engage the module is provided. The module includes an open mounting side configured for mounting the spring-clamping device.
The present invention not only makes the assembly easier because of the possibility of using preassembled modules but also simplifies the structural design of the cage clamp and the arrangement. Retaining tongues on the cage clamp which require an additional production step can be dispensed with. The modular design and faster installation times resulting from the present invention are advantageous. The present invention is based on the principle of identical parts or type case principle. It is also advantageous that both cage clamps and screw clamps can be used in a simple manner. A special cost reduction results from the fact that the basic housing, into which are inserted either the cage clamps or the screw clamps, can be jointly used. This reduces warehousing and production costs. No separate injection molds are required for the spring-clamping technology and the screw technology. Moreover, the present invention allows the two technologies to be integrated without additional expenditure. Moreover, by using the modules, it is advantageously possible to use standard cage clamps. The shape of the module can be adapted to the cage clamp design in a simple manner.
Due to the fact that the modules can be engaged in a receiving shaft, the electrical insulation requirements are fulfilled by the side walls of the receiving shaft. At the same time, it is possible, for example, to design the respective module in such a manner that it is open on one side.
Due to the arrangement inside the receiving shaft, the open side of the module is covered. The snap-in capability of the module simplifies the assembly. Therefore, it is particularly convenient if the module has snap-in noses which are able to snap into snap-in openings located in side walls of the receiving shaft.
It is particularly advantageous if the receiving shaft is at least partially open at a front side, the open front side being at least partially closed by a covering region or by a cover. This allows cable connection both from above and from the side.
The assembly of the module is simplified if the module has a covering region featuring guide ribs, the covering region being wider than the receiving shaft.
A particularly convenient embodiment of the module, a secure clamping technology and ease of electrical contacting are provided if the module has a contact piece located between a cage clamp and two supporting regions, a cable contacting chamber existing between the supporting regions, if the contact piece is brought out at the side opposite the cable opening side, if the contact piece has curved contact ends, and if the contact piece has a crank between its connecting end and the cable contact region, the connecting end being brought out of the module.
The connection of cables is made easier in that a cable connection chamber is provided next to the receiving means, the cable connection chamber being open at the bottom and suitable both for a connecting end of a cage clamp and for a connecting piece of a base contact element.